174 U.S. NATIONAL MUSEUM BULLETIN 227 



The worm has considerable powers of dispersal as indicated by its 

 daylight crawling on exposed intertidal areas, its nocturnal swimming, 

 and the swarming and spawning during the reproductive period. It 

 swims actively and is carried by winds, tides, and currents, and dis- 

 persed over wide areas. It can withstand considerable changes in 

 salinity from strictly marine to estuarine conditions. It has been 

 collected high intertidally and dredged down to 84 fathoms. 



Material examined.- — Numerous specimens Gulf of St. Lawrence 

 (Bay of Chaleurs, St. Lawrence estuary, Anticosti Island), Nova 

 Scotia (Bay of Fundy), Newfoundland, New Bruns\\-ick (Harvey in 

 Salisbury Bay, St. Andrews, Grand Manan) , Maine (St. Croix River, 

 Machias Bay, Penobscot Bay, Boothbay Harbor region, Casco Bay, 

 Sea Point near Kittery), New Hampshire (Oyster Kiver, Belamy 

 River, Little Harbor, Sagamore Creek, Rye Harbor, Hampton Har- 

 bor), Massachusetts (Plum Island, Essex, Marblehead, Scituate, 

 Annisquam River, Cape Ann, Woods Hole region, Megansett estuary, 

 Elizabeth Islands, Martha's Vineyard, Cape Cod), Rhode Island 

 (Narragansett Bay, Green Pond, Potters Pond, Sakonnet Point). 



Distribution.- — Iceland, Norway, Ireland, North Sea to France, 

 Gulf of St. Lawrence, Newfoundland to Virginia. Low water to 84 

 fathoms; sexual forms at surface. 



Nereis {Hediste) diversicolor O. F. Miiller, 1776 



Figure 4:4,g,h 



Nereis diversicolor ? Hoagland, 1919, p. 574.— Fauvel, 1923, p. 344, fig. 133,a-/.— 

 Dehorne, 1925, p. 1141.— Herpin, 1926, pp. 18, 28, 88, 94, 118.— Thorson, 

 1946, p. 65, fig. 30.— Harley, 1950, p. 734.— Dales, 1950, p. 321; 1951, p. 

 131.— Wesenberg-Lund, 1950a, p. 56; 1950b, p. 42; 1951, p. 41; 1958, p. 26.— 

 Smidt, 1951, p. 48, figs. 17, 18.— Wells and Dales, 1951, p. 674.— Newell, 

 1954, p. 334.— Dales and Kennedy, 1954, p. 699.— Boguchi, 1954, p. 79.— 

 Smith, 1955a, p. 33; 1955b, p. 326; 1955c, p. 453; 1956, p. 81; 1958, p. 60.— 

 Berkeley and Berkeley, 1956b, p. 267, fig. 3. — J0rgensen and Dales, 1957, 

 p. 357.— Stickney, 1959, pp. 17, 18.— Clark, 1960, p. 19. 



Neanihes diversicolor Hartman, 1960a, p. 35 (part). 



Description. — Length up to 200 mm., width up to 10 mm., seg- 

 ments up to 120. Body thickened, turgid anteriorly, flattened pos- 

 teriorly. Tentacular cirri slender, tapering, longest extending to 

 setigers 5-7. Parapodia clifTer only slightly from anterior to posterior 

 end. In the anterior segments (fig. 44f/), parapodia with 3 notopodial 

 ligules, upper one larger, triangular; lower one shorter, conical; middle 

 or presetal one still shorter, conical. Setigerous lobe of neuropodia 

 with two thick lips, postsetal lip or ligule slight! j^ longer, conical; 

 presetal lip short, bluntly rounded, with a conical lower ligule. No- 

 tosetae homogomph spinigers. Upper group of neurosetae homo- 

 gomph spinigers and heterogomph falcigers with rather long blades; 



